1. Field of the Invention
The present invention relates to a serial printing apparatus in which the font wheel and the carriage are stopped before each printing action, and more particularly to such printing apparatus capable of printing form lines. The present invention relates to a printing device capable of detecting information such as an end point of and several species of ink ribbon.
2. Description of the Prior Art
The conventional large word processor with a cathode ray tube display is bulky, expensive and requires expertise in use. Also there are known electronic typewriters which function as small word processors but they are still associated with various shortcomings requiring improvements and are complicated and expensive in structure. Further, the ink ribbons employed in the printing devices have different feeds amounts according to the species of ribbon. A so-called one-time typing ribbon can be used only once and is fed each time by an amount approximately equal to one character. On the other hand so-called multiple typing ribbon is usable several times and is advanced each time by an amount corresponding to 1/2 to 1/3 of one character. For this reason, a printing device designed for using these different species of ink ribbons needs to have an adjustable feed for the ink ribbon, and there also is required a means for detecting the species of the ink ribbon.
Also when using an ink ribbon it has been necessary to detect a suitable changing time for the ink ribbon, for example the arrival time of an end point of ink ribbon at the printing position, in order to maintain a satisfactory print quality. In this manner the conventional printing devices utilizing ink ribbons have required the detection of a plurality of information concerning the ink ribbon. Thus, these devices have required plural detecting means, which leads to a larger sized device and a higher cost for making the device. Besides such detecting means, which are usually composed of contact-type elements such as microswitches, are unstable and usually result in a complicated structure.